The present disclosure relates to a sensor system and method for monitoring a powertrain, in particular a powertrain comprising a drive shaft.
A powertrain or propulsion system is typically used to transfer mechanical energy into movement, for example movement of a vehicle, aircraft, or ship. A powertrain is formed by the main components that generate power and deliver it e.g. to the road surface, water, or air. This may include e.g. an engine, drive shaft, and final drive. A drive shaft or propulsion shaft is a mechanical component for transmitting torque and rotation between components of a powertrain, e.g. between the engine and final drive, or components there between. The final drive may e.g. include wheels, propellers, etcetera that interact with the environment to cause movement.
When a drive shaft is subjected to mechanical forces such as torque and thrust, these can result in small longitudinal and/or torsional strains (or angular displacement) at the surface of the shaft. These strains or deformations can be a measure for efficiency of the propulsion system. However, effectively detecting torsional torque and longitudinal strain of a rotating shaft member can be difficult to implement. This is a particular problem in the shipping industry where such measuring and monitoring systems typically operate in a harsh or hostile environment. Moreover for ship owners ensuring the propulsion shaft is operating correctly can be important to ensure optimum operating of the ship's engine thus minimizing fuel consumption and maintenance costs.
For example, German patent publication number DE 10 2008 014 644, describes a system with a fibre optic cable having fibre Bragg sensors for measuring properties of a drive shaft to operate a propeller. According to the prior art, the sensors are preferably mounted in or on a (hollow) drive shaft to reduce space outside of the shaft. However, it can be difficult to measure small deformations of the drive shaft. According to the prior art, an optic fibre is wrapped around a shaft in such way that it defines three sections: a first section longitudinal to the shaft, a second section wherein two parts of the fibre are orthogonal to one another and a twist wherein a section is radial to the shaft. However, the known system may be complex to install and prone to installation errors that would lead to erroneous measurements. Furthermore, the known system may have difficulty distinguishing different types of deformation, e.g. separating torsion, bend, and axial deformations.
Accordingly, it is desired to provide an improved sensor system and method for monitoring a powertrain having a drive shaft wherein one or more problems associated with the prior art are alleviated while maintaining at least some of the advantages.